The invention relates to a colour display tube comprising a glass envelope having a substantially rectangular display window includng an upright edge, having chamber-like recesses in the corners. The recesses are utilized to attach a substantially rectangular colour selection electrode which has cooperating suspension means in the corners.
Such a colour display tube is disclosed in U.S. Pat. No. 3,548,235. The display tube disclosed in the Patent comprises a display window with an upright edge having chamber-like recesses in the corners in. The corners of the colour selection electrode are attached to strip-shaped suspension members which are connected to clamping springs for insertion in the chamber-like recesses in the display window where they engage the walls of the recesses.
During insertion and removal of the clamping springs in, scratches easily occur on the walls of the recesses. Since the action of the clamping springs is based on friction, a large clamping force is required to obtain a good resistance to shocks of the tube. As a result of this large clamping force, stresses occur in the glass. This increases the possibility of fracture during the customary temperature treatments to which the display tube are subjected during manufacture. Furthermore, mediocre assembly reproducibility is obtained in such a tube when the clamping springs are repeatedly inserted in and removed from the recesses, as is necessary in the so-called flow-coating.